221313213 has 24 divisors (see below), whose sum is σ = 355324320. Its totient is φ = 131595360.

The previous prime is 221313193. The next prime is 221313227. The reversal of 221313213 is 312313122.

It is a de Polignac number, because none of the positive numbers 2^k-221313213 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221313263) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15843 + ... + 26336.

It is an arithmetic number, because the mean of its divisors is an integer number (14805180).

Almost surely, 2^221313213 is an apocalyptic number.

It is an amenable number.

221313213 is a deficient number, since it is larger than the sum of its proper divisors (134011107).

221313213 is a wasteful number, since it uses less digits than its factorization.

221313213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42249 (or 42246 counting only the distinct ones).

The product of its digits is 216, while the sum is 18.

The square root of 221313213 is about 14876.5995106409. The cubic root of 221313213 is about 604.8798459109.

Adding to 221313213 its reverse (312313122), we get a palindrome (533626335).

Subtracting 221313213 from its reverse (312313122), we obtain a palindrome (90999909).

The spelling of 221313213 in words is "two hundred twenty-one million, three hundred thirteen thousand, two hundred thirteen".